In 4.8 we changed the raster engine's handling of subpixel positioning to be more in line with floating point drawing systems, like GL and VG. The cosmetic line algorithm, drawLine_midpoint_i does not support this mode so we currently have some non-straight edges where outlines are not correctly aligned to the polygon edge. The outlineFillConsistency autotest in qpainter is currently disabled as a result of it.